PROJECT SUMMARY Despite decades of research, cancer is the Number 1 killer of adults under 85. Thus, there remains a substantial need for new therapies grounded in mechanisms that the non-malignant cellular microenvironment uses to prevent and control cancer. In direct response to that need, this revised, renewal application seeks to continue the highly successful, multidisciplinary UCLA Tumor Immunology Training Program (UCLA TITP). The TITP, as the sole training program at UCLA that integrates oncology with immunology, aims to provide comprehensive, interdisciplinary training to graduate students and post-doctoral fellows at the cancer-immune system interface to foster immune approaches that prevent and control cancer. An equally important aim is to prepare a well-trained cohort of experts, via augmented professional development activities, for productive careers in a rapidly evolving job market as leaders in academic and commercial tumor immunology. It is an extraordinary time in oncology as advances in tumor immunology are leading progress against intractable cancers, with cell engineering and immune checkpoint inhibition at the cutting-edge. The TITP has superb institutional synergies with the NCI-designated Jonsson Comprehensive Cancer Center (JCCC), the UCLA Clinical Science Translational Institute (CTSI), the Parker Institute for Cancer Immunotherapy (PICI), the Graduate Programs in Bioscience (GPB), the UCLA-Caltech Medical Scientist Training Program (MSTP), and other exceptional campus research centers. The program Co-Directors have outstanding records of research productivity and trainee mentoring. Trainees are recruited from a large pool with emphasis placed on research integrity training, mentoring, and outreach to enhance diversity and underrepresented scientist participation. We propose to support 9 trainees (3 pre- and 6 post-docs, up to 3 years, with strong progress) in a structured program supervised by highly productive faculty. For this period, with an updated mentor corps, training is focused in 3 high-priority tracts: Cancer Immunotherapy, Immuno-Oncology, and Tumor Microenvironment. About 85% of past trainees continue cancer research careers in academia or industry. Over the past 6-months, we performed a rigorous self-evaluation with input from trainees, faculty, and internal advisors to generate a stronger program that fully aligns with expert reviewer comments. A continuing element is a leading-edge set of pre-doctoral course choices that builds knowledge in basic, translational, and clinical tumor immunology research. Other strong components include a monthly Research-in-Progress seminar series, annually updated Individual Development Plans (IDPs), an annual summer Program Retreat, and major campus symposia focused on cancer. Fundamental changes include establishing an External Advisory Board for program evaluation, trainee feedback and expert guidance, and a more clearly defined didactic program for post- doctoral trainees. Altogether, the TITP infrastructure supports an exciting, coherent, and interactive program that uniquely serves graduate and post-doctoral education and training in tumor immunology at UCLA.